Studies on the antihypertensive, antispasmodic, bronchodilator and hepatoprotective activities of the Carum copticum seed extract

This study describes the antihypertensive, antispasmodic, bronchodilator and hepatoprotective activities of the aqueous-methanolic extract of Carum copticum Benth. seeds (CSE) to rationalize some of its traditional uses. CSE (3-100 mg/kg) caused a dose-dependent fall in arterial blood pressure in anaesthetized rats. In isolated rabbit aorta and jejunum preparations, CSE (0.1-3.0 mg/ml) caused an inhibitory effect on the K+-induced contractions. The calcium channel blocking (CCB) effect was confirmed when CSE shifted the Ca2+ dose-response curves (DRCs) to right similar to verapamil. In isolated guinea-pig tracheal preparations, it caused inhibition of carbachol and K+-induced bronchoconstriction at 0.1-1.0 mg/ml as well as shifted the dose-response curves (DRCs) of carbachol and histamine to the right with suppression of maximum response suggestive of non-specific bronchodilator effect mediated possibly through CCB. Pretreatment of rats with CSE (500 mg/kg orally for 2 days at 12 h intervals) prevented paracetamol (640 mg/kg) and CCl4 (150 ml/kg)-induced rise in serum alkaline phosphatase (ALP) and aminotransferases (AST and ALT). The same dose of CSE was able to prevent the CCl4-induced prolongation in pentobarbital-induced sleeping time in mice confirming its hepatoprotectivity. These results indicate the presence of calcium antagonist(s) in Carum copticum seeds and thus provides sound mechanistic basis for some of their folkloric uses.     

Studies on spasmogenic and spasmolytic activities of Calendula officinalis flowers

The aqueous-ethanol extract of Calendula officinalis flowers (Co.Cr) was studied for its possible spasmolytic and spasmogenic effects in isolated gut preparations. In rabbit jejunum, Co.Cr caused a dose-dependent (0.03-3.0 mg/mL) relaxation of spontaneous and K+-induced contractions, suggestive of calcium channel blockade (CCB). In a few preparations, a mild non-reproducible spasmogenic effect was observed at lower doses, followed by relaxation. The CCB effect was confirmed when pretreatment of the jejunum preparations with Co.Cr produced a dose-dependent rightward shift in the Ca(++) dose-response curves, similar to that of verapamil. Activity-directed fractionation revealed that the spasmolytic activity of the plant was concentrated in its organic fractions. The aqueous fraction exhibited a marked atropine sensitive spasmogenic effect but was found to be devoid of any spasmolytic effect. These data indicate that the crude extract of Calendula officinalis flowers contains both spasmolytic and spasmogenic constituents, exhibiting these effects through calcium channel blocking and cholinergic activities and this study provides a scientific base for its traditional use in abdominal cramps and constipation.     

Studies on hepatoprotective, antispasmodic and calcium antagonist activities of the aqueous-methanol extract of Achillea millefolium

The crude extract of Achillea millefolium (Am.Cr) was studied for its possible hepatoprotective effect against d-galactosamine (d-GalN) and lipopolysaccharide (LPS) induced hepatitis in mice and antispasmodic effect in isolated gut preparations to rationalize some of the folklore uses. Co-administration of d-GalN (700 mg/kg) and LPS (25 microg/kg) produced 100% mortality in mice. Pre-treatment of animals with Am.Cr (300 mg/kg) reduced the mortality to 40%. Co-administration of d-GalN (700 mg/kg) and LPS (1 microg/kg) significantly raised the plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels compared with values in the control group (p < 0.05). Pre-treatment of mice with Am.Cr (150-600 mg/kg) significantly prevented the toxins induced rise in plasma ALT and AST (p < 0.05). The hepatoprotective effect of Am.Cr was further verified by histopathology of the liver, which showed improved architecture, absence of parenchymal congestion, decreased cellular swelling and apoptotic cells, compared with the toxin group of animals. In isolated rabbit jejunum preparations, Am.Cr caused a concentration-dependent (0.3-10 mg/mL) relaxation of both spontaneous and K(+)-induced contractions as well as shifting the Ca(++) concentration-response curves (CRCs) to the right, similar to that caused by verapamil. These results indicate that the crude extract of Achillea millefolium exhibits a hepatoprotective effect, which may be partly attributed to its observed calcium channel blocking activity.     

Anti-diarrheal and spasmolytic activities and acute toxicity study of Soonkijangquebo, a herbal anti-diarrheal formula

The anti-diarrheal and spasmolytic activities of Soonkijangquebo (SKJQB), a Korean herbal anti-diarrheal formulation, were subjected to pharmacological evaluation. SKJQB, at a dose of 50-200 mg/kg, inhibited castor oil-induced diarrhea in mice. The median effective dose (ED50) for the anti-diarrheal effect was 93 mg/kg. In isolated rabbit jejunum preparations, SKJQB produced a spasmolytic effect by the relaxation of spontaneous contractions in a dose-dependent manner. The median effective concentration (EC50) for the spasmolytic effect was 3.6 mg/ml. In isolated guinea pig ileum preparations, SKJQB also produced a spasmolytic effect by reduction of acetylcholine-induced contractions. When tested against calcium channel blockade in rabbit jejunum, SKJQB caused a dose-dependent rightward shift in the Ca2+ dose-response curves, similar to that produced by verapamil, a well-known calcium antagonist. In an acute toxicity study in Sprague-Dawley rats, the median lethal dose (LD50) of SKJQB was greater than 2000 mg/kg, and no pathological changes were noticed in macroscopic examination by necropsy of rats treated with SKJQB. Thus, SKJQB may be safely used as a spasmolytic as well as an anti-diarrheal agent.     

Antispasmodic and blood pressure lowering effects of Valeriana wallichii are mediated through K+ channel activation

Crude extract of Valeriana wallichii rhizome (Vw.Cr) and its fractions were studied for possible antispasmodic and blood pressure lowering activities to rationalize some of the folkloric uses. In rabbit jejunum preparations, Vw.Cr (0.1–3.0 mg/mL) caused relaxation of spontaneous contractions. When tested against high K⁺ (80 mM)-induced contractions it produced weak inhibitory effect, while caused complete relaxation of the contractions induced by low K⁺ (20 mM). In the presence of glibenclamide (3 μM), the inhibitory effect of low K⁺ was shifted to the right, similar to that produced by cromakalim while, verapamil caused no differentiation in its inhibitory effect against low and high K⁺-induced contractions. In guinea pig ileum, the plant extract produced similar results as in rabbit jejunum. Intravenous administration of Vw.Cr, produced fall in arterial blood pressure in normotensive anaesthetized rats and this effect was partially blocked by glibenclamide. In rabbit aortic preparations, plant extract also caused a selective and glibenclamide-sensitive relaxation of low K⁺ (20 mM)-induced contractions. Activity-directed fractionation studies revealed that the observed activity was distributed both in the chloroform and aqueous fractions. These results indicate that the antispasmodic and hypotensive effects of Valeriana wallichii are mediated possibly through K_ATP channel activation, which justify its use in gastrointestinal and cardiovascular disorders.     

Studies on antihypertensive and antispasmodic activities of methanol extract of Acacia nilotica pods

A methanol extract of Acacia nilotica pods (AN) caused a dose-dependent (3-30 mg/kg) fall in arterial blood pressure. Treatment of animals with atropine abolished the vasodilator response of acetylcholine (ACh), whereas the antihypertensive effect of the plant extract remained unaltered. Phentolamine (an alpha-adrenergic blocker) abolished the vasoconstrictor effect of norepinephrine (NE), whereas pretreatment of the animal with AN, did not modify the NE response. These results indicate that the antihypertensive effect of plant extract is independent of muscarinic receptor stimulation or adrenoceptor blockade. In the in vitro studies, AN produced a dose-dependent (0.3-3.0 mg/mL) inhibitory effect on force and rate of spontaneous contractions in guinea-pig paired atria. Similarly, it inhibited the spontaneous contraction of rabbit jejunum in a concentration-dependent (0.1-3.0 mg/mL) manner. AN also inhibited K(+)-induced contractions in rabbit jejunum at a similar concentration range, which suggests that the antispasmodic action of AN is mediated through calcium channel blockade, and this may also be responsible for the blood pressure lowering effect of AN, observed in the in vivo studies.     

Antispasmodic effect of Acorus calamus Linn. is mediated through calcium channel blockade

Acorus calamus Linn. (Araceae) is a native of Central Asia and Eastern Europe and has widespread use in the traditional system of medicine for gastrointestinal disorders such as colic pain and diarrhoea. This study was aimed at providing a possible pharmacological basis to the use of this plant as an antispasmodic and antidiarrhoeal. In the isolated rabbit jejunum preparation the crude extract (Ac.Cr), which tested positive for the presence of alkaloid, saponins and tannins, caused inhibition of spontaneous and high K(+) (80 mm)-induced contractions, with respective EC(50) values of 0.42 +/- 0.06 and 0.13 +/- 0.04 mg/mL (mean +/- SEM; n = 6-8), thus showing spasmolytic activity, mediated possibly through calcium channel blockade (CCB). The CCB activity was confirmed when pre-treatment of the tissue with Ac.Cr (0.3-1.0 mg/mL) caused a rightward shift in the Ca(++) dose-response curves similar to that caused by verapamil, a standard calcium channel blocker. Activity-directed fractionation revealed that the CCB activity was concentrated in the n-hexane fraction while the ethylacetate fraction was less potent. These results suggest that the spasmolytic effect of the plant extract is mediated through the presence of CCB-like constituent(s) which is concentrated in the n-hexane fraction and this study provides a strong mechanistic base for its traditional use in gastrointestinal disorders such as colic pain and diarrhoea.     

Antispasmodic activity of extracts and compounds of Acalypha phleoides Cav

The aerial parts of Acalypha phleoides are usually prescribed in the Mexican traditional medicine for a variety of gastrointestinal complaints. The MeOH-CHCl(3) (1:1) extract of the aerial part of A. phleoides showed an inhibitory effect on the gastrointestinal propulsion of a charcoal meal in mice. In isolated guinea-pig ileum, this extract produced a concentration dependent inhibition of the contractions induced by 5-hydroxytryptamine, but it was unable to inhibit the contractions elicited by acetylcholine, histamine, KCl and BaCl(2). This extract produced also a concentration dependent inhibition of the spontaneous pendular movement of the isolated rabbit jejunum. This inhibitory activity was partially blocked by propranolol. The essential oil, obtained from the aerial part of this plant, was more potent than the MeOH-CHCl(3) (1:1) extract in inhibiting the spontaneous pendular movement of the rabbit jejunum. Thymol, camphor and gamma-terpinene were identified from the essential oil by GC-MS. These monoterpenes showed antispasmodic activity in the rabbit jejunum preparation, thymol was the most active compound, followed by camphor and gamma-terpinene. Thymol and camphor in high concentrations also showed tracheal relaxant properties, but gamma-terpinene did not. These in vivo and in vitro results tend to support the traditional use of A. phleoides as an antispasmodic agent.     

The presence of cholinomimetic and calcium channel antagonist constituents in Piper betle Linn

The crude aqueous extract of Piper betle leaves (Pb.Cr) was studied for the possible presence of cholinomimetic and calcium channel antagonist constituents. Pb.Cr at doses of 1-10 mg/mL caused a moderate spasmogenic effect in isolated guinea-pig ileum and this activity was concentrated in the aqueous fraction, which was found to be about 5 times more potent. Pretreatment of the tissue with atropine (1 microM) but not hexamethonium (100 microM) completely abolished the contractile effect of the aqueous fraction indicating a cholinergic (muscarinic) mechanism. In isolated rabbit jejunum preparations Pb.Cr did not produce a significant increase in the spontaneous contractions, but instead produced a dose-dependent (0.03-3.0 mg/mL) inhibition of spontaneous activity. Activity-directed fractionation revealed that the spasmolytic action was concentrated in the ethyl acetate fraction. When tested against K(+)-induced contractions, both Pb.Cr and its ethyl acetate fraction (Pb.EtAc) caused a dose-dependent inhibition, suggesting calcium channel blockade (CCB). The potent CCB effect of the crude extract and its ethyl acetate fraction was confirmed when pretreatment of the tissue with Pb.Cr or Pb.EtAc shifted the Ca(++) dose-response curves to the right in a dose-dependent manner. These data indicate that the plant contains cholinomimetic and possible calcium channel antagonist constituents, which are concentrated in the aqueous and ethyl acetate fractions respectively. It is suggested that some of the traditional uses of this plant may be explained on the basis of these activities.     

Species Differences in the Antidiarrheal and Antispasmodic Activities of Lepidium sativum and Insight into Underlying Mechanisms

The aim of this study was to see if the crude extract of Lepidium sativum (Ls.Cr) exhibits species specificity in its antidiarrheal and antispasmodic activities along with insight into the underlying mechanisms using the in‐vivo and in‐vitro experiments. Ls.Cr inhibited castor oil‐induced diarrhea in mice at doses (300 and 1000 mg/kg) three times higher dose than for rats. In isolated rat ileum and jejunum, Ls.Cr completely inhibited carbachol (CCh), low K⁺ (25 mM) and high K⁺ (80 mM)‐induced contractions, while in guinea‐pig tissues, Ls.Cr caused complete inhibition of only CCh‐induced contraction. In rabbit tissues, Ls.Cr completely inhibited CCh and low K⁺‐induced contractions sensitive to K⁺ channel antagonists. Pretreatment of guinea‐pig and rat tissues with Ls.Cr caused a rightward shift in CCh‐induced contractions in a pattern similar to dicyclomine, while in rabbit and rat tissues, Ls.Cr shifted isoprenaline curves to the left similar to papaverine. These data indicate that the antidiarrheal and antispasmodic activities of L. sativum are species dependent, mediating its antispasmodic effect through combinations of multiple pathways including activation of K⁺ channels, and inhibition of muscarinic receptors, Ca⁺⁺ channels and PDE enzyme. Rat tissues showed the highest potency. Based on the results, we recommend using multiple species to know the real pharmacological profile of medicinal products. Copyright © 2012 John Wiley & Sons, Ltd.     

Cholinomimetic and calcium channel blocking activities of Carthamus oxycantha

The crude extract of Carthamus oxycantha (Co.Cr) and its fractions were studied in vitro for their possible spasmogenic and spasmolytic activities. Co.Cr (0.03-10 mg/mL) caused an atropine sensitive spasmogenic effect in guinea-pig ileum. In spontaneously contracting rabbit jejunum preparations, Co.Cr caused a dose-dependent (0.03-3.0 mg/mL) spasmogenic effect, followed by relaxation at the next higher doses of 5.0-10.0 mg/mL. In the presence of atropine, the spasmogenic effect was blocked and the relaxant effect was observed at lower doses (0.1-5.0 mg/mL), shifting the inhibitory dose-response curves to the left. Co.Cr also inhibited K(+) (80 mm)-induced contractions in atropinized preparations at similar doses, suggesting calcium channel blockade (CCB) activity. The CCB effect was further confirmed when pretreatment of the tissue with Co.Cr produced a dose-dependent shift in the Ca(++) dose-response curves to the right, similar to that caused by verapamil. Activity-directed fractionation revealed that the spasmolytic effect was concentrated in organic fractions in the following order of potency: hexane > ethylacetate > chloroform, while the aqueous fraction exhibited spasmogenic and weak spasmolytic effects. These results indicate that Carthamus oxycantha contains a combination of spasmogenic (cholinergic) and spasmolytic (calcium antagonist) constituents.     

Effects of an aqueous extract of Ferula ovina on rabbit and guinea pig smooth muscle

The effects of an aqueous extract of Ferula ovina were tested in vitro using isolated segments of rabbit and guinea pig intestine, trachea and aorta. The extract inhibited the spontaneous movements of rabbit jejunum and guinea pig ileum and the contractions induced by acetylcholine. The aqueous extract also inhibited the contractions of rabbit trachealis muscle induced by acetylcholine and the contractions of guinea pig trachealis muscle induced by histamine. These inhibitions were dose-dependent and reversible. However, the aqueous extract did not inhibit the contractions of rabbit and guinea pig aortic rings induced by norepinephrine. These data suggest that this plant has non-specific anticholinergic and antihistaminic antispasmodic effects.     

Presence of blood‐pressure lowering and spasmolytic constituents in Buddleja crispa

This aim of this study was to investigate the crude extract of Buddleja crispa (Bc.Cr) and its active constituent(s) for their antihypertensive and antispasmodic activities. The Bc.Cr caused a dose‐dependent (3–10 mg/kg) fall in mean arterial pressure in rats under anesthesia. In rabbit aorta preparations, Bc.Cr (0.03–1 mg/mL) caused inhibition of high K⁺ (80 mM) precontractions. The Bc.Cr (0.03–1 mg/mL) also inhibited spontaneous and high K⁺ precontractions in rabbit jejunum preparations, suggestive of calcium channel blocking (CCB) activity. CCB activity was further confirmed when pretreatment of the tissues with Bc.Cr (0.03–0.10 mg/mL) caused a rightward shift in Ca⁺⁺ concentration response curves, similar to verapamil. Among the pure compounds, BdI‐H3 was more potent against the high K⁺ than spontaneous contractions and was around eight times more potent than Bc.Cr against the spontaneous contractions while the other two compounds, BdI‐2 and BH‐3 were inactive. Activity‐directed fractionation revealed that the hexane fraction was more potent against K⁺ precontractions. These data indicate that Bc.Cr possesses a blood‐pressure lowering effect, mediated possibly through CCB, though additional mechanism(s) cannot be ruled out. Among the pure compounds, Bdl‐H3 is likely to be the active compound involved in the spasmolytic and possibly BP lowering effect of the parent crude extract. Copyright © 2008 John Wiley & Sons, Ltd.     

Antidiarrhoeal and spasmolytic activities of the methanolic crude extract of Alstonia scholaris L. are mediated through calcium channel blockade

This study was aimed to provide a pharmacological basis to the medicinal use of Alstonia scholaris as an antidiarrhoeal and antispasmodic by using in vivo and in vitro techniques. In the in vivo study the crude extract of Alstonia scholaris (As.Cr), which tested positive for the presence of alkaloids, provided 31–84% protection against castor oil‐induced diarrhoea in mice at 100–1000 mg/kg doses, similar to loperamide. In isolated rabbit jejunum preparation, the As.Cr caused inhibition of spontaneous and high K⁺ (80 mm )‐induced contractions, with respective EC₅₀ values of 1.04 (0.73–1.48) and 1.02 mg/mL (0.56–1.84; 95% CI), thus showing spasmolytic activity mediated possibly through calcium channel blockade (CCB). The CCB activity was further confirmed when pretreatment of the tissue with the As.Cr (0.3–1 mg/mL) caused a rightward shift in the Ca⁺⁺ concentration‐response curves similar to verapamil, a standard calcium channel blocker. Loperamide also inhibited spontaneous and high K⁺ precontractions as well as shifted the Ca⁺⁺ CRCs to the right. These results indicate that the crude extract of Alstonia scholaris possesses antidiarrhoeal and spasmolytic effects, mediated possibly through the presence of CCB‐like constituent(s) and this study provides a mechanistic base for its medicinal use in diarrhoea and colic. Copyright © 2009 John Wiley & Sons, Ltd.     

Antidiarrheal and Antispasmodic Activities of Buddleja polystachya are Mediated Through Dual Inhibition of Ca++ Influx and Phosphodiesterase Enzyme

This study describes the antidiarrheal and antispasmodic activities of the hydro‐alcoholic extract of Buddleja polystachya (Bp.Cr) with possible mode of action explored along with activity‐directed fractionation. Bp.Cr and its aqueous (Bp.Aq) and organic fractions, petroleum ether (Bp.Pet), dichloromethane (Bp.DCM), ethylacetate (Bp.EtAc) and butanol (Bp.But), were tested using the in‐vivo and in‐vitro assays. The crude extract (100–300 mg/kg) showed 20 and 60% protection of castor oil‐induced diarrhea in mice. In isolated rabbit jejunum, Bp.Cr like papaverine inhibited spontaneous and high K⁺ (80 mM)‐induced contractions equi‐potently. In guinea‐pig ileum, Bp.Cr showed a moderate spasmogenic effect. The activity‐directed fractionation revealed that the spasmolytic activity was concentrated in the organic fractions and spasmogenic component in the aqueous fraction. Amongst the organic fractions, BP.DCM and Bp.Pet inhibited spontaneous and high K⁺‐induced contractions equi‐potently, while Bp.But, like verapamil was more potent against high K⁺. The crude extract and its organic fractions caused rightward shift in the Ca⁺⁺‐concentration response curves (CRCs), similar to verapamil, and all except Bp.But potentiated the isoprenaline‐inhibitory CRCs to the left, similar to papaverine. The results of this study indicate that the crude extract of B. polystachya possesses antidiarrheal and antispasmodic activities, mediated possibly through dual inhibition of Ca⁺⁺ influx and phospodiesterase enzyme. Copyright © 2015 John Wiley & Sons, Ltd.     

Anticonvulsant activity of aqueous root extract of Ficus religiosa

Ethnopharmacological relevance

Ficus religiosa Linn is frequently used for the treatment of nervous disorders among Pawara tribe of the Satpuda range, India.

Aim of the study

This study aimed to investigate the anticonvulsant activity of the aqueous aerial root extract of Ficus religiosa in chemoconvulsant-induced seizures in mice.

Materials and methods

The anticonvulsant activity of the extract (25, 50 and 100 mg/kg, p.o.) was investigated in strychnine-, pentylenetetrazole-, picrotoxin- and isoniazid-induced seizures in mice. Rat ileum and fundus strip preparations were used to study the effect of the extract on acetylcholine (Ach)- and serotonin (5-HT)-induced contractions, respectively.

Results

The extract showed no toxicity and protected the animals in the strychnine and pentylenetetrazole tests in a dose-dependent manner. Its effect in the picrotoxin and isoniazid tests, however, was less potent. The extract also exhibited dose-dependent potentiation of Ach in rat ileum but failed to potentiate the effect of 5-HT in rat fundus strip preparation.

Conclusions

The results suggest that an orally administered aqueous root extract of Ficus religiosa has dose-dependent and potent anticonvulsant activities against strychnine- and pentylenetetrazole-induced seizures. The observed activities may be ascribed to the appreciable content of zinc and magnesium in the extract.     

Ethnopharmacological studies on antispasmodic and antiplatelet activities of Ficus carica

ETHNOPHARMACOLOGICAL RELEVANCE: The ripe dried fruit of Ficus carica Linn. (Moraceae) commonly known as "Fig" has medicinal value in traditional system of medicine for its use in gastrointestinal and inflammatory disorders. AIM OF THE STUDY: To rationalize the medicinal use of Fig (Ficus carica) in gastrointestinal and inflammatory disorders. MATERIALS AND METHODS: The aqueous-ethanolic extract of Ficus carica (Fc.Cr) was studied for antispasmodic effect on the isolated rabbit jejunum preparations and for antiplatelet effect using ex vivo model of human platelets. RESULTS: Fc.Cr tested positive for alkaloids, flavonoids, coumarins, saponins, sterols and terpenes. When tested in isolated rabbit jejunum, Fc.Cr (0.1-3.0mg/mL) produced relaxation of spontaneous and low K(+) (25mM)-induced contractions with negligible effect on high K(+) (80mM) similar to that caused by cromakalim. Pretreatment of the tissue with glibenclamide caused rightward shift in the curves of low K(+)-induced contractions. Similarly, cromakalim inhibited the contractions induced by low K(+), but not of high K(+), while verapamil equally inhibited the contractions of K(+) at both concentrations. Fc.Cr (0.6 and 0.12mg/mL) inhibited the adenosine 5'-diphosphate and adrenaline-induced human platelet aggregation. CONCLUSION: This study showed the presence of spasmolytic activity in the ripe dried fruit of Ficus carica possibly mediated through the activation of K(+)(ATP) channels along with antiplatelet activity which provides sound pharmacological basis for its medicinal use in the gut motility and inflammatory disorders.     

Pharmacological investigations on Achyrocline satureioides (LAM.) DC., Compositae

Achyrocline satureioides (Lam.) DC. inflorescences have been used as remedies in folk medicine for the treatment of a variety of human ailments, particularly those of the gastrointestinal tract. Different extracts of inflorescences have been tested for anti-inflammatory, analgesic, antispasmodic, constipating and sedative activities. The aqueous extracts (maceration and decoction) and ethanolic macerate exhibited an inhibition of the carrageenan-induced rat paw oedema at a dose range of 75-500 mg kg-1 i.p., and also showed analgesic effect with the acetic acid-induced writhing test in mice. The gastrointestinal propulsion of a charcoal suspension was not affected significantly by any extract, at a dose of 200 mg kg-1 p.o., in mice. The aqueous decoction increased pentobarbital-induced sleeping time, at doses of 200 and 500 mg kg-1 i.p. and p.o., in mice. The ethanolic macerate inhibited contractions induced by acetylcholine, histamine, noradrenaline and barium chloride in four different smooth muscle tissues. The antispasmodic and anti-inflammatory activities were reproduced with quercetin, luteolin and quercetin 3-methyl ether, flavonoids that have been isolated from this plant. A partial evaluation of the toxicity of the extracts was also performed. The pharmacological effects assayed are discussed in relation to the chemical constituents of this plant and its popular use in gastrointestinal disturbances, and inflammatory conditions could be related to the presence of the flavonoids.     

Pharmacological effects of the aqueous extract of Neorautanenia mitis in rodents

The pharmacological effects of the aqueous extract of Neorautanenia mitis (family Papilonaceae) were studied in rodents. Investigations were carried out on acetic acid-induced writhing (pain) in mice and hind paw oedema in rats. The effects of the extract were also studied on the isolated non-pregnant rat uterus and rabbit jejunum. Results showed the extract to possess significant (P<0.05) dose-dependent anti-nociceptive activity between 12.5 and 50.0 mg/kg p.o. in mice and slight anti-inflammatory activity at 25 and 50 mg/kg p.o. in rats. The extract also produced a concentration-dependent inhibition of the normal rhythmic contraction of the isolated non-pregnant rat uterus. It was found to inhibit oxytocin-induced as well as acetylcholine-induced contractions in the rat uterus. The extract also exhibited concentration-dependent inhibition of spontaneous contractions of the rabbit jejunum. Preliminary phytochemical analysis of the extract revealed the presence of saponin glycosides, flavonoids, tannins and alkaloids. The extract had an intraperitoneal (i.p.) LD(50) of 282.84+/-3.2 mg/kg in mice. These data corroborate the traditional use of this plant in the treatment of dysmenorrhea.     

Pharmacological basis for the use of peach leaves in constipation

The aqueous crude extract (PPL.Cr) of peach leaves (Prunus persica) was studied for the possible presence of gut stimulatory constituent(s) to rationalize the folkloric use of the plant in constipation. PPL.Cr at the dose of 1-10 mg/ml caused a moderate degree of spasmogenic effect in isolated guinea-pig ileum. Pretreatment of the tissue with atropine (1 M) completely abolished the contractile effect of the plant extract similar to that of acetylcholine which is suggestive of a cholinergic mechanism. In isolated rabbit jejunum preparations, PPL.Cr produced a week spasmogenic effect followed by relaxation of the spontaneous contractions at higher doses. Bioassay-directed fractionation revealed that the spasmogenic activity was separated in the aqueous fraction, while the spasmolytic activity was concentrated in the ethyl acetate fraction. When tested against K(+)-induced contraction, both PPL.Cr and its ethyl acetate fraction (PPL.EtAc) caused a dose-dependent inhibition, suggesting calcium channel blockade (CCB). The presence of CCB in peach leaves was confirmed when pretreatment of the tissue with PPL.EtAc caused a dose-dependent rightward shift in the Ca(2+) dose-response curves, similar to that produced by verapamil. These data indicate that the plant contains spasmogenic (cholinomimetic) and spasmolytic (calcium antagonist) constituents, which are concentrated in the aqueous and ethyl acetate fractions, respectively. Furthermore, the laxative effect of the plant reported in the traditional system of medicine may be partially due to the cholinergic action, which was dominant over the spasmolytic component.